Dialkylaminoaryl arylcarbamates



United States Patent 3,125,593 DIALKYLAMINOARYL ARYLCARBAMATES EngelbertKiihle, Cologne-Stammheirn, and Ludwig Eue,

Cologne-Mullreim, Germany, assiguors to Farbenfabrilren BayerAktiengesellschaft, Leverkusen, Germany,

a corporation of German N0 Drawing. Filed Nov. 30, 1959, Ser. No.855,989 Claims priority, application Germany Dec. 6, 1958 4 Claims. (Cl.260-471) The present invention relates to and has as its objects new anduseful compounds with herbicidal activities, and processes for theirproduction. Generally the new compounds are condensation products ofisocyanates with such aromatic compounds containing at least one freehydroxyl group and in addition thereto at least one tertiary aminomethyl group being either in oor p-position.

Certain ureas and carbamates are already known to be effective andpowerful herbicides. Thus e.g. p-chlorophenyl dimethyl urea (CMU) aherbicide which became of major practical importance during the lastyears, as well as the m-chloro-phenyl carbamic acid isopropyl ester(CIPC) are widely used as a herbicide, especially for the germinatingcontrol of potatoes.

The condensation products of the present invention are also carbamateswhich distinguish themselves from those compounds previously known by abasic substituent. The new carbamic acid derivatives of the presentapplication more specifically may be shown by the following generalformula NCHa R OCN H R n O H m I in which R stands for aromatic oraromatic-heterocyclic radicals, R and R stand for lower alkyl radicals,R is an aromatic or an aliphatic radical, and n is a whole number from 1to 3, and m is a whole number from 1 to 2.

The preparation of the new compounds starts from known condensationproducts of Mannich-type, i.e. of condensation products of phenols Withformaldehyde and secondary amines. It is known that regarding the numberand position of other substituents of a benzene nucleus up to 3 aminomethyl groups may be introduced by this way in a benzenic ring system.Thus e.g. phenol itself reacts with formaldehyde and dimethyl amine,giving 2,4,6-tris-(dimethyl-aminomethyl)-phenol.

Further preparation of the inventive compounds starts from these Mannichcondensation products by various possible ways. Thus e.g. the compoundsof the Mannichtype may be reacted with isocyanates to the new inventivecarbamic acid derivatives. This reaction is to be seen from thefollowing scheme in which the symbols have the same significance asgiven above:

As it has been said before the carbamic compounds containing at leastone free hydroxyl group must at least have an amino-methyl group eitherin oor p-position.

3,125,598 Patented Mar. 17, 1964 "ice groups, alkoXy-groups,carbalkoXy-groups, and the like. It has to be understood that not only1, but more than 1 free OH-group may be present in the molecule of thestarting material. The second reaction component of the above equation,namely the isocyanate compound may be of aliphatic, cycle-aliphatic,heterocyclic or aromatic nature and may be a monoor poly-isocyanate. Ifpoly-isocyanates are used the above shown end product is a diorpolycarbamic acid ester. Examples for isocyanates are methyl-isocyanate,ethyl-isocyanate, pro pyl isocyanate, hexyl isocyanate,w-chlorohexyl-isocyanate, cyclohexyl-isocyanate, phenyl-isocyanate, 0-,mand p-chlorophenyl-isocyanate, the various lower alkoxyphenyl-isocyanates, the different nitro-phenyl-isocyanates, uandfi-naphthyl-isocyanate (possibly further substituted),hexamethylene-diisocyanate, the various phenylene-diisocyanates, thevarious naphthyl-diisocyanates, and the like.

The reaction shown by the above formula usually starts at roomtemperature or even at lower temperatures and is exothermic. It might beadvantageous to carry out the inventive reaction in suitable inertorganic solvents such as lower aliphatic ketone (acetone), benzene,toluene, chloro-benzene, and the like. In other cases it might be betterto react the free components without any solvent at all. Mostly reactionshould be carried out with equimolecular amounts of starting materials,i.e. reacting 1 isocyanate group with a hydroxyl group. If compoundswith more hydroxyl groups and more than 1 isocyanate groups are reactedand compounds containing in the end material such free groups are desred then reaction in a known equimolecular proportion might lead to thedesired result.

The new compounds of the present invention prepared by this way usuallyare known undistillable slightly colored oils or resins. As Mannichbases of aromatic nature they decompose while heating.

A preferred method of preparing stable salts of the inventive compoundswith organic acids consists in carrying out the above shown reaction infree aliphatic carbonic acids such as formic acid, acetic acid,propionic acid, methoXy-acetic acid, chloro-acetic acid, dichloroaceticacid, trichloro-acetic acid, fumaric acid, cytric acid, maleic acid, andthe like. In this case the Mannich-basesalts of those acids areobtained. If the acids used in excess are easily distillable the excessof acids might be removed by distillation if necessary in vacuum, thusyielding the pure salts of the above shown Mannich bases. If these saltsare desired in addition to the acid also inert organic solvents mayadditionally be used for completion of the aforedescribed reaction. Incase of using additionally inorganic solvents the desired acid might beused in about equimolecular proportions.

Other known Ways for preparing the inventive compounds are reacting thefree hydroxy group containing Mannich-bases with carbamic acid chloridesas it is to be seen from the following equation: 1

Another way for obtaining the inventive compounds with the reaction ofthe hydroxyl groups containing Mannich-bases with phosgene and furtherreaction of 3,125,598 3 d the formic acid ester chlorides with suitableprimary Example 2 amines is as it is to be seen from the followingequation: 30 grams of 2 4 6 tri (diethy1 aminomethyl) phenol aredissolved in 50 ml. of acetone whereupon 10 grams R C Q1 of phenylisocyanate dissolved in 10 ml. of acetone are R2 added dropwise. Afterthe slightly exothermic reaction HN has slowed down the reactionsolution is concentrated in vacuum. The 2,4,6-tri-(diethylamino-methyD-phen- R R yl-N-phenyl-carbamic acid remains as a darkyellow colored oil. The yield is almost quantitative.

2- The following analytical data show the identity of 2 n this compound:C H N O The symbols in these formulae again have the same ggff gg gFound significance as said above.

The new products of the present invention distinguish 15 2 i g i the ifg i g g themselves mostly by herbicidal activities; they are either cuat mo 5 o e y lsocyana e em 15 0 mm total herbicides or selectiveherbicides. Other compounds the following compound:

are fungicides and at last the new products of this in- C zN zHs) zvention may be used as intermediates in the synthetic OQHE l resinfield- N-CHg-O-CNHCgH5 If used as herbicides or fungicides use of theabove ll compounds of the present invention is achieved by 2 5 waysknown in principle i.e. by admixing the active i-M 2 5):

ingredients with inert diluents or carriers either solid or liquid andthen applying these mixtures or carriers Example? where undesired plantshave to be destroyed. Suitable 35 grams of 2,4,6-tri-(diethylaminomethyl)-phenol solid diluents or extenders are e.g. talc, chalk,bentonite, are dissolved in 100 ml. of acetone whereupon a soluclay,fullers earth, silica, and the like. Liquid formution of 8.4 grams ofhexamethylene diisocyanate in lations are mainly of aqueous nature. Ifnecessary auxml. of acetone is added. The temperature slowly risesiliary solvents such as dimethyl formamide or acetone 30 to about 30 C.Stirring is continued for a short time are necessary. Also addition ofsuitable emulsifiers and the solution then is concentrated in vacuum. 44might be advantageous; such emulsifiers which are mostgrams of thecorresponding carbamate are obtained. The

ly of known ionic type and which mainly consist of following analyticaldata show the identity of the compolyglycol ethers of aromatic compoundssuch as nonyl pound: C I-1 N 0 phenyl polyglycol ether, are benzylhydroxy diphenyl Calc.: C, 69.3%; H, 10.40%; N, 12.92%. Found:

polyglycol ether. C, 69.9%; H, 9.57%; N, 12.38%.

The following examples may illustrate the present in- By using theequimolecular amount of o-phenylene vention without, however, limitingthe present invendiisocyanate there is obtained the correspondingcomtion thereto. pound of the following formula C 2N t) 2 C HiN- (0 H 2C113 CH, O-%HN -NHCO -OHi-N OHQ), egg 0 Q JH N CH) CH2-N( s)2 2- a 2Example 1 Example 4 20 grams of 2,4,6-tri-(dimethyl aminomethyl)-phenol9 g a o imethyl- -(dimethyl amino methyl)- are dissolved in ml. ofacetone and then treated at 50 P l are diss lved in 75 ml. of acetonewhereupon room temperature with 9 grams of phenyl isocyanate. grams of py isocyanate are added- Aft r the re- The reaction is exothermic and thetemperature rises to action has bfien completed the Solution is freedfrom about 35 C. The reaction mixture i ti d for a acetone bydistillation at last in vacuum. There are obshort time and then theacetone is distilled off. There tamed 145 grams of the Corresponding -Pfl are bt i d 29 grams f h 2 4. 6 i-(di h 1 i bamate in the form of aresinous oil. Analytical data: methyl)-phenyl-N-phenyl-carbamic acid.Analysis of C1SH22N2O2- this compound showed the following results:Calc.: C, 72.5%; H, Found: C,

Calculated: C, 68.8%; H, 8.32%; N, 14.6. Found: 72.l%; ,7.44%; C, 68.8%;H, 8.50%; N, 143%, If instead of phenyl isocyanate 3,4-dichlorophenyliso- By the same way th r ar obt i d f o 2,4,6, t -icyanate are used thefollowing compound is obtained: (dimethyl aminornethyl)-phenol with thefollowing iso- H g CH N(CHE),

O1 cyanates the corresponding carbamic acid esters which i IsocyanateSummary Reaction product 5 a l formula (analysis) Example 5 16.5 gramsof 4-methyl-6-(dimethyl aminomethyl)- Q ClaHitNtOfl-n gigg g fif phenolare dissolved in 100 ml. of acetone and then Found: 0, 685%; treatedslowly while stirring with 11.9 grams of phenyl g gisocyanate. Stirringis continued for some time where- HsCzO-NOO C nnamon Calc.: o, 67.5%; H,upon the solvent is distilled off at last in vacuum. There gZ areobtained 26 grams of a yellowish oil which has been H, 8.99%; 'N,identified by the following analysis: C H N O 13-04% Calc.: C, 71.8%; H,7.04%; N, 9.86%. Found: C,

If instead of phenyl isocyanate the isocyanates shown in the followingtable are used in the same manner as described above there are obtainedthe compounds shown in the table below and identified by the followinganalysis:

Reaction product Summary (analysis) Isoeyanate formula OzHsNC O GIG-NCO.

Example 6 C1a 20N:O2 Calc.: C,

8.47%; N, Found: C, 66.8%; H, 9.09%; N, 12.10%.

Calc.: C,

5.10%. Found: C 59.5%; H, 5.60%.

Isocyanate Summary Reaction product formula (analysis) 02H5NCO CmHnNaOg0810.! N, 14.35%.

Found: N, 14.47%. 01

| Cl-NCO... o20H,,o12N.0.- Calc.: o1,17.ao%.

Found: 01, 17.55%.

Example 7.

21 grams of 4-acetylamino-6-(dimethylaminomethyl)- phenol are dissolvedin 150 ml. of acetone. While stirring there are added slowly 18.8 gramsof 3,4-dichlorophenyl isocyanate. The solvent is distilled oil in vacuumand there are obtained 40 grams of a resinous oil which is identified byanalysis.

Calc.: C, 54.6%; H, 4.79%; Cl: 17.9%. Found: C, 54.9%; H, 5.21%; Cl,17.3%.

Example 8 18.5 grams of 4-chloro-6-(dimethylaminomethyl)- phenol aredissolved in 150 ml. of acetone, whereupon 12 grams of phenyl isocyanateare added slowly while stirring the reaction mixture. The temperatureslowly rises to 30 C. After stirring is continued for some time thesolvent is distilled off at last in vacuum whereupon 30 grams of aresinous oil are obtained. Identification by analysis showed thefollowing results: C H ClN O Calc.: C, 63.0%; H, 5.58%; N, 9.20%. Found:C, 62.2%; H, 5.60%; N, 9.23%.

In the same way but using instead of phenyl isocyanate the correspondingequimolecular amount of .ethyl isocyanate there is obtained thefollowing compound identified by analysis:

Calc.: C, 56.2%; H, 6.62%; N, 10.92%. Found: C, 56.4%; H, 6.73%; N,9.80%.

Example 9 22 grams of 2,4-dichloro-6-(dimethylaminomethyl)- phenol aredissolved in 150 ml. of acetone and treated slowly while stirring with12 grams of phenyl isocyanate. After the reaction has slowed down thesolvent is distilled off at last in vacuum whereupon 33 grams of areddish oily product are obtained. Identification has been carried outby analysis: C H Cl N O Calc.: C, 56.7%; H, 4.73%; Cl, 20.94%. 55.4%; H,4.50%; Cl, 23.10%.

Example 10 20 grams of l-(dimethylaminomethyl)-2-naphthol are dissolvedin ml. of acetone whereupon 7 grams of ethyl isocyanate are added slowlywhile stirring. The mixture rises above 30 C. The reaction is completedby further stirring for 30 minutes and the solution then is concentratedat last in vacuum. 25 grams of an oily product of the following formularemain:

Found: C,

Example 11 22.4 grams of 2,5-bis-(dimethylarninomethyl)-hydroquinone aresuspended in ml. of acetone. To the suspension there are added at roomtemperature dropwise and While stirring a solution of 12 grams of phenylisocyanate in 30 ml. of acetone. The temperature rises to about 30 C.Stirring is continued for 1 further hour. The reaction productprecipitates and amounts to 22 grams and is isolated by filtration withsuction. It melts r at 136 C., and is a compound of the followingformula:

1 Mona).

By the same way but using 2 molecular equivalents of phenyl isocyanatethere is obtained the bis-urethane melting at 144 C.:

onhmonm Gaiaa AJHr-N (0 a) 2 Example 12 20 grams of 7-dimethylaminomethyl-8-hydroxyquinoline are dissolved in 100 ml. of acetone and thentreated slowly with 12 grams of phenyl isocyanate dissolved in 30 ml. ofacetone. The reaction mixture after some further stirring is continuedin vacuum. The oily residue slowly solidifies and amounts to 32 grams.The crude product which is almost pure melts between 95-100 C.

The reaction product may be shown by the following for mula:

Example 14 20 grams of l-(dimethylaminomethyl)-2-naphthol are dissolvedin 50 ml. of triethyl amine. Below 15 C. there are added while stirring12 grams of phenyl isocyanate. The reaction product of the followingformula crystallizes soon and may be isolated by filtration. Byconcentration of the mother liquor the further crop of reaction productmay be obtained. There are obtained 26 grams of the aforeshown carbamicacid ester melting at 90- 95 C.

Example 15 40 grams of l-(dimethylarninomethyl)-2-naphthol are dissolvedin 100 ml. of acetic acid; while stirring there are added dropwise at 45C. 24 grams of phenyl isocyanate. The temperature rises to about 50 C.Stirring is continued for some time and the acetic acid in excess isdistilled off in vacuum. The acetate of the compound shown in theforegoing example is obtained in an amount of 73 grams.

Example 16 40 grams of l-(dimethylaminomethyl)-2-naphthol are dissolvedin 100 ml. of acetic acid, and while stirring there are added at 45 C.31 grams of p-chlorophenyl isocyanate dissolved in 20 ml. of acetone.The temperature rises to about 48 C. After distilling off the solvent invacuum there are obtained 72 grams of the acetate ofN-(p-chlorophenyl)-carbamic acid-2- l-dimethylaminomethyl) -naphthyl]-ester.

Example 17 35.8 grams of 3,5-dimethyl-6-(dimethylaminomethyl)- phenolare dissolved in 80 ml. of acetic acid at 40 C. and then treateddropwise while stirring with a solution of 31 grams of p-chlorophenylisocyanate in 20 ml. of acetone. After completion of the reaction thesolvent is distilled oh in vacuum whereupon there are obtained 72 gramsof N-(p-chlorophenyl)-carbamic acid[3,5-dimethyl-6-(dimethylaminomethyl)-phenyl]-ester as its acetate.

To demonstrate the utility of the compounds of this invention thefollowing examples are given:

Example 18 Mixed cultures of mustard and oat are sprayed with aqueousemulsions containing an active compound of Example 1 in a concentrationof 0.05%. The aqueous emulsion as been prepared by mixing same amountsof active ingredient and acetone adding thereto the same amount ofcommercial nonionic emulsifier (nonyl phenol polyglycol ether-MPC). Thismixture then is diluted to the above said concentration.

Mustard and oat are completely destroyed thereby.

Similar results are obtained with the other compounds described in theforegoing examples.

Example 19 Mixed cultures of mustard and cat are sprayed with aqueousemulsions as described in the foregoing example, 24 hours after sowing.The amount of active ingredient (of Example 1) used per hectare shouldamount to 1.5 kg. per hectare; 10 days after treatment the young mustardplants begin to die and the oats showed chlorosis. 3 weeks later all theplants are completely destroyed. The other compounds shown in theexamples exhibit similar properties.

Example 20 If bush bean plants (Vitia faba) are sprayed with a 0.1%aqueous solution of the compound of Example 1 (the solution beingprepared as described in Example 18). The plants lose their leaveswithin 24 to 36 hours. The compound thus acts also as a defoliant ordesiccant.

We claim:

1. A compound of the formula NCHzR-OCN 2 0 \H wherein R and R stand forlower alkyl, R stands for a member selected from the group consisting ofphenyl and chlorophenyl and R is selected from the group consisting ofdimethyl phenylene and naphthyl.

2. The compound of the following formula i 0 H3O OHZN (CH3): 3. Thecompound of the following formula CH3 Cl GH2N( a)2 4. The compound ofthe following formula References Cited in the file of this patent UNITEDSTATES PATENTS 2,362,508 Stevens et al Nov. 14, 1944 2,843,519 FitchJuly 15, 1958 FOREIGN PATENTS 185,371 Austria Apr. 25, 1956 OTHERREFERENCES Kolbenzen et al.: J. A. and Food Ohem., 2,866, 869, 870(1954).

1. A COMPOUND OF THE FORMULA